added way to completely disable printouts

unittest/internal/UnittDefinitions.cpp

@@ -3,7 +3,9 @@
  ReturnValue_t unitt::put_error(std::string errorId) {
 #if FSFW_CPP_OSTREAM_ENABLED == 1
 	sif::error << "Unit Tester error: Failed at test ID "
-			<< errorId << "\n" << std::flush;
-#endif
+			<< errorId << std::endl;
+#else
+	fsfw::printError("Unit Tester error: Failed at test ID 0x%08x", errorId);
+#endif /* FSFW_CPP_OSTREAM_ENABLED == 1 */
 	return HasReturnvaluesIF::RETURN_FAILED;
 }

unittest/internal/UnittDefinitions.h

@@ -2,7 +2,7 @@
 #define UNITTEST_INTERNAL_UNITTDEFINITIONS_H_
 
 #include "../../returnvalues/HasReturnvaluesIF.h"
-#include "../../serviceinterface/ServiceInterfaceStream.h"
+#include "../../serviceinterface/ServiceInterface.h"
 #include <cstdint>
 #include <cstddef>
 #include <string>